Mauser Muzzle Protector
I looked in a few of my books on the Swede 94's and 94/17's and they show two different muzzle protectors. Both of the 94 & 94/17 have a flush barrel with the protector. In another book they show a barrel extension.
The book "The Swedish Mauser Rifles" 2nd Edition by Joe Poyer he shows a barrel flush with the protector.
The other book "Guns of the World" by Bonanza Books Page 181 Published in 1977. They explain why the barrels are extended due to early US Federal requirements for rifle barrel lengths to be over 18".
The examples shown don't have a stepped extension just the barrel protruding through the end cap.
The Argentine 1909 carbine has the exact end cap as shown here. An excellent picture of the Argentine 1909 carbine muzzle extension in the new book from Men At Arms, "Bolt Action Military Rifles of the World" page 291.
It was introduced in 1926.
The new book "Bolt Action Military Rifles of the World" is an excellent reference book. My wife ordered it and the book on the 1888 rifle from Joesalter.com.
Great books and must have to enlarge a firearms library.